The Importance of Remote Sensing: An Interview With David McLelland

Interview conducted by Will SoutterJul 13 2012

Insights from Industry: David McLelland, appointed Director of Auracle Geospatial Science Inc., discusses the environmental and cost benefits of remote sensing in the mining industry and how it has progressed over time.

Could you please provide a brief introduction to Auracle Geospatial Science and the sector which it works within?

AGS is a remote sensing company which also undertakes some GIS for our clients. The sector that we work within is the mineral exploration, mining, oil and gas sector. We predominantly focus our work within the exploration end, but we do also work with producers.

How does AGS work within the mining industry?

Our remote sensing processes include data fusion methodologies, in order to assist in the exploration for mineralization, both pervasive and anomalous. We produce high resolution models, delineating revealed lineaments and classify revealed fused spectra.

We usually develop a phased plan of remote sensing analyses. Our analyses are validated by ground truthing data which we then use for ongoing supervised classification to iteratively improve results.

When people acquire image data and do remote sensing, one of the first fruits is geographic evidence. Remote sensing analysis can form an environmental baseline and evidence, from the onset, of the status of the area or project.

A 3-D model produced by AGS. Image Credit: AGS

Could you outline your remote sensing processes and how these benefit the mining industry?

Each project is unique and has special considerations that we work out with our clients. However, we’ve developed protocols that guide our work.

We begin with the acquisition of multivariate sets of satellite image data and the collection of applicable archived geoscience data, which we spatially integrate and pre-process in preparation for data driven and knowledge based data fusion. It’s a complex process but fusing these data creates a large single data set which contains the imagery and mathematical significance of the whole of the data, while reducing their dimensionality and reducing signal noise.

As fused data, their statistical relationships can be examined, revealed and modelled. We relate the resulting signals to phenomena such as mineralization, alteration and lithology through the use of experience-based analysis, standard spectral libraries and structural model typing. By combining digital terrain data with the linear, textural, and classification features of remote sensing data results we are typically able to resolve accurate project scale maps including non- apparent stratigraphic contacts, and non- apparent or blind mineralization.

Could you provide an example that further explains this process?

We recently fused multivariate image multi-temporal spectral satellite data, radar sat panchromatic data and knowledge based geological data to produce a new type of image of the area.

These new images more clearly identified fault structures, rock lithologies and alterations that are not visible on simple satellite images, aerial Lidar images or geological maps. Using these textural and colour patterns, we can quickly categorize their area of interest and refine their mapping. We help them to identify structures and alterations that have the highest probabilities of containing mineralized areas so that they can concentrate on more detailed exploration on the targeted regions.

A spectral classification map. Image Credit: AGS

Could you provide a brief overview of GIS mapping and the need for this is the mining industry?

Geographic Information Systems (GIS) is an essential tool for natural resource management as it makes it possible to organize and store vast amounts of geographic information. Most exploration companies, for example, have moved away from manually produced maps to powerful digital map databases.

Everything we do in remote sensing ends up in a GIS. The real advantage to GIS, in my view, is that it is an interdisciplinary tool that makes it possible for geochemists, geophysicist, structural geologists and businessmen to talk to each other about the same project easily using images rather than technical language. It usually provides the opportunity for people to come up with collaborative ideas.

How are AGS unique in the services that they provide?

Our results can be presented in a technical report and digital and mapped data derivatives, depending on the client’s needs.

Generally, we provide Digital Elevation Models, topographic maps, structural (fracture lineament) models, mineral and alternation spectra maps, and thermal anomaly maps. These are all orthorectified and georeferenced to meet or exceed the mapping standards of the company or country we are working for.

What is unusual about our work is that we are typically able to identify and map things that are otherwise considered to be blind. We can identify structures that are discontinuous at surface but that may be seen in radar or alteration chemistries that cannot be seen visibly without specialised equipment. Another example is an alteration mineral, like Buddingtonite, which can be a pathfinder indicator for mineral deposits, which cannot be seen by geologists with the unaided eye.

What are some of the other important geospatial solutions that AGS provides?

We also use expert geoscientists who can go out into the field and test the target areas to refine the process. By doing this, we can increase the resolution of our models and also reduce or increase the probability of likelihood in our spectral models.

We are also in the last stage of developing a UAV-based hyper-spectral system.

What target mineral deposit types can remote sensing be employed for?

Our techniques can be used on most deposits types. We’ve had great success working on kimberlites, VMS, surficial uranium and a wide variety of other deposits.

We can also work with industrial minerals, as well as oil and gas.

Are the services you provide of use at every stage of mine development? Is there an optimum stage of proceeding at which your services are of most use?

We can help at all stages, but we typically come in during early exploration. It is most advantageous to come in as early as possible. Companies benefit by having a robust, stable geospatial database to rely on throughout their exploration and development work.

Can the services that AGS offer be beneficial to the environment?

Remote Sensing is an efficient way to gather and analyze vast amounts of information from large areas, “at a distance” that is, without having to be physically on the ground. This is very significant because it allows us to provide highly detailed and accurate classifications and maps of remote areas throughout the world before anyone considers setting foot on the ground. The benefits to the environment are pretty dramatic. We have the belief that every time we work we save thousands of gallons of jet fuel.

But it is not just fuel savings alone. The human footprint is also drastically reduced as we take very large areas and with our clients, condense them into much smaller target areas of exploration, reducing the amount of travel that needs to take place into those areas and the amount of actual intrusion on the land and surrounding communities.

How do companies benefit from your services?

Many exploration companies have gotten caught in long delays and red-tape associated with getting licenses and permits required to get into or to work in an area. The first benefit is that remote sensing doesn’t require social license or a permit so it’s something that can be done immediately. There is no additional licensing or permitting costs. We are typically able to start on a project the minute we have approval from our clients. That’s a critical advantage.

The other important advantage is that we are able to do these things in virtually all weather. We can use archive data in most cases. We can do work on Greenland in the middle of winter!

Orthorectified Radarsat-1F Imagery. Image credit: AGS

Do you perform these solutions across the globe?

Locations vary from year to year. At the moment we are doing a lot of work in Greenland, Labrador, Newfoundland, Central Canada, the Northwest Territories, Africa, South America, and southern US. So we are definitely a global company!

How has remote sensing and geospatial technology changed over the last decade and how will it progress in your opinion in the next 10 years?

When I first started in this business, it could take up to 11 hours to process some of our simple data but now with our super computers, we can do the same work in much less time so the cost to clients has been greatly reduced.

The internet has had an incredible effect on all of the image processing fields. People from one field, be it microscopy, medical imaging or geophysics, will look at something and see a similarity that no one has detected before. The capacity and applications have really taken off. Also, as a result of the internet and the expansion in the distribution of information, there is far less focus on the protection of intellectual property and far more focus on research and development.

Our field is moving extremely quickly, with ever evolving processes and increasing resolutions. There is a dramatic increase in data dimensionality. The industry is dealing with very large and varied data sets and it is exciting to see the response in technology and research.